Homeopathy is often criticized for having little research evidence available. This blog is a compilation of what I have learned in examining research evidence for homeopathy published in conventional medical journals. For more info on homeopathy, please see a previous blog entitled “Homeopathy primer.”

One of the major reasons that the results of most mainstream research on homeopathy are often inconclusive because the methods used usually do not honour the principles of homeopathy and therefore the research does not actually evaluate the practice of homeopathy. Aphorism 104 in the Organon explains how a practitioner can take and treat a case homeopathically:

“Once the totality of symptoms that principally determine and distinguish the disease case … has been exactly recorded, the most difficult work is done … He can then select … a well-aimed, similar, artificial disease potence, in the form of a homeopathically chosen medicinal means, to oppose the total disease image (1).”

Unfortunately, remedies are often not prescribed individually and are instead selected based on typical clinical presentation of pathology.

A meta-analysis published by Shang et al. in the Lancet in 2005 compared placebo-controlled homeopathy trials to conventional medicine trials matched by disorder and type and determined that “the clinical effects of homoeopathy, but not those of conventional medicine, are unspeciﬁc placebo or context effects (2).” The homeopathy trials were categorized classical, clinical, or complex homoeopathy (or as isopathy). Specifically,

“Classical homoeopathy was deﬁned as comprehensive homoeopathic history-taking, followed by the prescription of a single individualised remedy, possibly with subsequent change of remedy in response to changing symptoms. If no comprehensive homoeopathic history was taken and all patients received a single, identical remedy, interventions were classiﬁed as clinical homoeopathy (2).”

Only “classical” homeopathy trials actually reflect the use of remedies according to homeopathic principles as set out in the Organon. “Clinical” homeopathy is the substitution of homeopathic remedies for conventional medicine and therefore not the practice of homeopathy. Of 110 homeopathy trials analyzed, only 18 were categorized as “classical” while 48 “clinical” homeopathy trials were analyzed. The selection of trials for this analysis therefore precluded results that would accurately evaluate the effects of homeopathic treatment.

Rutten and Stolper analyzed post-publication data from the Shang paper and concluded that:

“Re-analysis of Shang's post-publication data did not support the conclusion that homeopathy is a placebo effect. The conclusion that homeopathy is and that conventional is not a placebo effect was not based on comparative analysis and not justified because of heterogeneity and lack of sensitivity analysis. If we confine ourselves to the predefined hypotheses and the part of the analysis that is indeed comparative, the conclusion should be that quality of homeopathic trials is better than of conventional trials, for all trials (p=0.03) as well as for smaller trials (p=0.003) (3).”

A review by Lüdtke and Rutten also came to this conclusion. Their meta-analysis determined that “homeopathy had a significant effect beyond placebo (OR=0.76; 95% CI: 0.59-0.99; p=0.039) (4).” and that, “Shang's negative results were mainly influenced by one single trial (4).” They concluded: “Shang's results and conclusions are less definite than had been presented (4).”

Linde et al. published a review of randomized controlled trials of individualized homeopathy in the Lancet in 1998. In this review, the team clarified that, “in individualized homeopathy the choice of the remedy for treatment is not based on a conventional diagnosis but on the match of the patient’s particular symptoms with the ‘remedy picture (5)’” and also conceded that, “no attempt was made to assess the ‘homeopathic’ quality of the trials. The reviewer’s knowledge and experience homeopathy are insufficient for such judgments (5).” While recognizing their limited comprehension of homeopathy, Linde et al. reviewed 32 studies, providing detailed information about each study’s methodology, including whether remedies were indeed prescribed homeopathically:

“In 20 trials, the choice of the remedy seemed to be unrestricted (approach 1), in 2 trials patients were included only if they matched the remedy picture of one of a preset range of remedies (approach 2), in 7 studies patients were included (without taking into account "homeopathic" aspects) and then the best fitting remedy had to be chosen from a range of predefined remedies was prescribed (approach 3), and in 3 trials only one remedy was applied and patients were entered only if they matched the remedy picture (approach 4) (5).”

Only 19 trials provided “sufficient data for meta-analysis (5),” although not all of these trials were of high methodological quality nor did all of them use individualized therapy. Of 12 trials categorized as “likely to have good methodological quality” or “unlikely to have major flaws,” all except two favoured homeopathy over placebo (5). Of these 12 highest quality trials, seven were individualized, and all except one favoured homeopathy. This review relied on the data from the 19 trials (both individualized and otherwise) and concluded: “while overall the results indicate that individualized homeopathy is superior to placebo, the methodologically better trials have less positive results and confirmatory independent replications are lacking. The evidence from these trials that individualized is clearly more efficacious than placebo is, therefore, not fully convincing (5).”

This review, which recognized individualization of treatment in homeopathy, is a step in the right direction. Conducting useful research on homeopathy within the conventional medical paradigm requires a greater understanding of the system of medicine being investigated in order to truly evaluate the use of homeopathy as a treatment modality.

Finally, a long-term observational study by Witt et al. assessed perceived change in complaint severity and quality of life at baseline, and after 2 and 8 years in 3,709 patients treated with homeopathy. In this study, physicians were free to choose treatment which “usually included the prescription of homeopathic medicines according to homeopathic principles, but also could include the onset, change, or withdrawal of a conventional medicine, referrals to specialists, or admission to a hospital (6).” At eight years, 32.9% of patients were still receiving homeopathic treatment, 29.2% of patients stopped treatment due to perceived major improvements in health, 26.0% stopped treatment because they did not feel homeopathy helped enough, 7.1% of patients stopped treatment for reasons unrelated to efficacy of therapy, and 3.6% stopped treatment without reason (6). The researchers concluded that, “patients who seek homeopathic treatment are likely to improve considerably, although this effect must not be attributed to homeopathic treatment alone. These effects persisted for 8 years (6).”